---
slug: 01-prompt-engineering-theory
role: index
date: 2026-04-21
---

> **📅 Research snapshot as of 2026-04-21.** Provider pricing, free-tier availability, and model capabilities drift every quarter. The router reads `data/routing-table.json` and `data/model-registry.json` at runtime — treat those as source of truth. If this document disagrees with the registry, the registry wins.

# Category 01 — Prompt Engineering Theory

Foundational prompt-engineering mechanics: classifier-free guidance (CFG), negative prompts, cross-attention control, prompt weighting syntax, LLM-driven prompt expansion, and the surveys that frame them.

## Angles

| File | Topic |
|---|---|
| [`1a-cfg-and-negative-prompts.md`](./1a-cfg-and-negative-prompts.md) | Classifier-free guidance, CFG scaling, negative prompts |
| [`1b-compositional-attention-control.md`](./1b-compositional-attention-control.md) | Compositional & attribute prompting, attention manipulation |
| [`1c-llm-prompt-expansion.md`](./1c-llm-prompt-expansion.md) | LLM-assisted prompt expansion & decomposition |
| [`1d-prompt-weighting-syntax.md`](./1d-prompt-weighting-syntax.md) | Prompt weighting syntax across ecosystems |
| [`1e-survey-papers.md`](./1e-survey-papers.md) | Survey & review papers on T2I prompt engineering (2023-2026) |

## Also in this folder

- [`SYNTHESIS.md`](./SYNTHESIS.md) — synthesized insights across angles

## Up one level

- [`../index.md`](../index.md) — master research index
- [`../SYNTHESIS.md`](../SYNTHESIS.md) — master synthesis
